Since at least the 1990s, researchers have been exploring the idea that people form actual relationships to brands, and that the language may not entirely be metaphorical, Susan Fournier, a professor of marketing at Boston University, told Science of Us. Fournier helped pioneer this area of research back in 1998, with the publication in the Journal of Consumer Research of a handful of case studies examining the “committed partnerships” that some people form with certainbrands.

In the ensuing years, researchers have followed up on that paper — which has been cited in the literature at least 5,000 times, as The Atlantic noted in an interview with Fournier — and the results help shed some light on the psychic pain some Volkswagen drivers are feeling now. Brands can break your heart, at least in part because the emotions we experience for them are very real, and in some cases even comparable to the way we feel about some of the people in ourlives.

This, on its surface, sounds nutty, Fournier allows. “It seems irrational to say that. Like, Are you serious? Do I have a relationship with Tide laundry detergent?” she said. “No person on the planet is going to say, ‘Yeah, I guess I do.’ … So that’s where the role of the researcher comes in.” And some, including a trio of scientists in Germany, are coming up with some pretty weird attempts at measuring the love people have for brands in an empirical way. In a recent paper titled “Is It Really Love?” these researchers wanted to compare brand love to human love, and they came up with some surprisingresults.

In one experiment, they attached electrodes to the skin of 20 participants so they could measure their level of physiological arousal, and then showed them four images: two pictures of people (one whom they loved and another whom they very much liked), and two pictures of products (again, one they loved and another they liked). They found that people responded differently when shown pictures of a beloved person and a beloved brand, with significantly greater skin arousal (sweating, warmth) occurring when they looked at the picture of the person compared to the product. The love we feel for people is — of course — stronger than the love we feel for stuff, even at a physiologicallevel.

But a funny thing happened when they compared participants’ skin response to pictures of beloved brands and their reactions to the images of their good pals: They found no significant differences in skin arousal. It is, of course, true that this is just a physiological response, which a number of things can elicit. But the researchers argue that, if we don’t quite fall in love with brands, we are at least capable of falling in deep like with some ofthem.

On the other hand, a newer mode of thinking is emerging in consumer psychology, one that suggests fanboys and fangirls don’t perceive their beloved brand as a relationship; some may consider it an extension of themselves. In 2012, University of Illinois researchers published the results of a study in which they first assessed the level of their study volunteers’ attachment to a brand; next they showed the participants critical statements about the company. Afterward, those who were most attached to the brand reported lower self-esteem than those who were less attached. So this means that some people, the authors claim, start to incorporate their love for Apple or Xbox into their ownidentity.

And this idea may help explain the deep emotional reactions some people have when a brand betrays their trust. The authors of one recent paper in the Journal of Consumer Research argue that people feel ashamed and insecure when a company betrayal is discovered, much like what would happen when trust is broken in an interpersonal relationship, precisely because of the fact that their self-concept has been tied up with their products. And this might be particularly true in the case of the Volkswagen emissions scandal, Fournier said. “These are people going out of their way to make a statement about their social conscious nature,” she said. “And those identities are so strong, and they’re visible — people use them asbadges.

“And now this violation goes to the heart of that — you’ve been driving around a fraud,” she continued. “It doesn’t save the world from being polluted, it doesn’t help the planet. I mean, that, to me, is one of the most egregious betrayals I’ve seenever.”

We’ll see in the coming days and weeks the ways Volkswagen will attempt to woo back its customer base, but the thing about things is they’re replaceable. One recent study found that when people find suitable substitutes for products they loved (including Facebook and Snickers) their loyalty for their once-favorites quickly dwindled, within a matter of days. It’s another similarity to interpersonal relationships: The heart has a way ofhealing.